This invention relates to a cutting edge arrangement comprising multiple plates, each plate having a cutting edge along one side, the plates joined together with the cutting edges aligned parallel to each other and slightly offset in a direction perpendicular to the cutting edges so that only one cutting plate forms the outermost edge, wherein said plates may be removed one by one to maintain a sharp cutting edge.
There are many known tools which have cutting edges, such as knives, razors, scissors, and various cutting blades. These conventional edged tools have to be sharpened in order to maintain a sharp cutting edge. Sharpening can be an inconvenient process, such as when a sharpener is not readily available. Sharpening may also be a difficult or impossible process, in the case of very hard materials, such as stainless steel.
The object of this invention is to provide a cutting edge arrangement that does not require sharpening in order to maintain a sharp edge.
This object has been achieved according to the present invention by providing a cutting edge arrangement comprising multiple cutting plates, each cutting plate having two opposing planar surfaces and having a cutting edge along an edge. The cutting plates are bonded together along facing planar surfaces with the cutting edges aligned parallel to each other and slightly offset in a direction perpendicular to the cutting edges. When the outermost edge of the cutting edge arrangement becomes dull, the cutting plate having that dull cutting edge may be removed so that the next cutting plate, having a sharp cutting edge, becomes the new outermost edge of the cutting edge arrangement. As each succeeding outermost edge of the cutting edge arrangement becomes dull, the cutting plate corresponding to that dull cutting edge is removed. In this way, a sharp cutting edge is maintained without sharpening. Any number of cutting plates may be used, the number of cutting plates determining the useful life of the cutting edge arrangement.
There are various methods which may be used to construct the cutting edge arrangements. In a first method, each cutting plate with a cutting edge is formed separately, and then the cutting plates are bonded together with the cutting edges parallel and slightly offset in a direction generally perpendicular to the cutting edges. Alternatively, the cutting plates may be bonded together first, and then the cutting edges may be formed at the edge of each plate. Yet another method of construction is to first bond together large plates, then form the cutting plates out of bonded plates. In this method, the cutting edges may either be formed at the time the plates are formed, or in a separate step afterwards.
In one preferred embodiment of the present invention in the form of a knife, a base plate is formed preferably of steel or stainless steel preferably having a thickness of 1.5 to 2.0 millimeters. The base plate is connected at one end to a handle. Ten to twenty cutting plates preferably each having a thickness of 0.15 to 0.20 millimeters and each having a cutting edge are bonded to the base plate. The cutting edge of each succeeding cutting plate extends slightly, preferably within the range of 0.2 to 1.5 millimeters, beyond the cutting edge of the previous plate to which it is bonded in a direction generally perpendicular to the cutting edges. In an especially preferred embodiment of the present invention, the cutting edge of each succeeding cutting plate extends within the range of 0.5 to 1.0 millimeters. The cutting plates are preferably made of steel or stainless steel, but may be made of ceramic material which is reinforced with a very thin metal or fiber sheet. A portion of each cutting plate, proximate the handle, is not bonded to aid in the removal of the cutting plates. An area of the non-bonded portion of each cutting plate, is separated from the next cutting plate to allow the cutting plate to be gripped with a tool to be removed. A non-toxic bonding material is used which preferably can be stripped off along with the cutting plate.
In another embodiment of the present invention in the form of a knife, a base plate is connected at one end to the handle. Cutting plates are attached to the base plate magnetically, by magnetizing successive plates with opposite magnetic poles at the ends. In this embodiment, it is preferable that the cutting plates be coated with oil to prevent corrosion from water or other liquids between the cutting plates. In this embodiment, a stopping portion contains the edges of the cutting plates opposite the cutting edges, which may be connected to or integral with the base plate.
In another embodiment of the present invention in the form of a scissors, two cutting edge arrangements having base plates and laminated bodies are rotatably connected. The laminated bodies comprise multiple cutting plates which have cutting edges on one side. The cutting edge arrangements are rotatably connected by a pin member extending through a hole in a central region of each arrangement, with the cutting edges of the first arrangement facing the cutting edges of the second arrangement. Handles are attached to ends of the base plates opposite the laminated bodies.
The cutting edge arrangement of the present invention may also be used for razors, cutting blades, or any other tool which has a cutting edge.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.